The threat of even worse disruption on the railways has increased after train drivers at four companies backed strike action in the industry-wide fight for pay awards in line with the rate of inflation.

The Aslef drivers union said its members at four train companies have voted in favour of strikes, with four more ballots still being counted.

Another union, the TSSA, is expected to add to the numbers backing industrial action when the result of a ballot of its members at Network Rail is announced – also expected on Monday.

The votes follow highly disruptive strikes by 40,000 RMT union workers across 13 operators and at Network Rail last month.

Talks to avert further walkouts in that dispute are set to continue this week.

In making its case for strikes, Aslef said its members were seeking their first pay rise since 2019 after increases lagged the rate of inflation.

It is currently at a 40-year high of 9.1% and tipped to exceed 11% in the autumn amid an energy cost-driven price surge across the economy.

Aslef general secretary, Mick Whelan, said: “We will fight to maintain the pay, terms and conditions, and the pensions of our members. The train companies are doing very well out of Britain’s railways – with handsome profits, dividends for shareholders, and big salaries for managers – and train drivers are not going to work longer for less.

“We’re not asking for a pay rise. We’re asking for our pay not to be cut for the third year in a row.

“We’ve accepted real-term pay cuts for two or three years now, but whilst huge sums of money continue to slosh around our industry, we won’t accept another cut for another year.

“Wage increases aren’t the main cause of inflation. Excess profiteering is. Wages are chasing inflation, not causing it.”